I take systems from zero, or from someone else's prototype, to production, and keep them running.
Since 2023 I've built and maintained production platforms for European enterprise clients at a software consultancy, owning them end to end: data model, APIs, frontend, CI and releases, security and production fixes. Outside work I'm going deep on distributed systems, building them in the open.
A self-hosted, language-agnostic job queue server in Go, backed by PostgreSQL. Producers enqueue jobs; workers lease, run and acknowledge them, with at-least-once delivery.
available ──lease──> leased ──ack──> completed
^ │
├─ nack / expired ─┤ after backoff
│ │
│ └─── max attempts ──> dead
│ │
└──────────────── redrive ────────────────┘
Every job is one row in Postgres; these are its states.
Leases with heartbeats and per-lease fencing tokens, so a worker that lost its job can't acknowledge it.
Retries with exponential backoff and jitter, a dead-letter queue, delayed jobs and strict priorities.
Long-poll leasing woken by LISTEN/NOTIFY, served over gRPC and HTTP/JSON from one protobuf definition.
A Go SDK whose workers keep one long-poll per process sized to free slots, and shut down gracefully.
Operations: cancel jobs, page through and redrive the dead-letter queue, prune old jobs, and push back on producers when a queue is full.
Correctness: invariant and chaos tests kill workers and servers, freeze a worker and restart Postgres, then check that no job was lost or completed twice.
A one-command Docker demo with two servers behind Envoy and a Grafana dashboard: kill a worker or a server and watch the jobs recover.
Next: tracing, a load test, TypeScript and C# SDKs, then a Raft-replicated store underneath.
Production platforms for European enterprise clients, at a software consultancy, since 2023. The code is private; here is what I did.
Advisor-recruitment platform
2026 – present
NestJS · Next.js · PostgreSQL (Supabase)
Built about 95% of it single-handedly, backend and frontend, replacing a manual recruitment workflow. In production since May 2026.
Designed the PostgreSQL schema, REST APIs, authentication and the candidate workflow state machine. Integrated Microsoft Dataverse, Adobe Sign, WooCommerce, Power BI and OpenAI.
Led a security overhaul: framework upgrades, a strict nonce-based CSP, a fix for a PostgREST filter-injection risk, secret scanning and a clean dependency audit.
Customer-retention app
2026 – present
Fastify · React · PostgreSQL · Azure
Took over a prototype built by the client and brought it through UAT to production in under four weeks.
Own the codebase, releases and all feature work: secrets in Azure Key Vault, verified TLS to the database, logging and an admin maintenance mode.
Built transactional email in German, French and Italian, with a staging sandbox that runs the real flow but can never reach a customer.
Advisor-hiring and product-demo platform
2025 – present
Angular · TypeScript · .NET backend
A long-running production system with 8,000+ advisors onboarded and 300,000+ customers.
I own the Angular frontend: production fixes, maintenance and the client's ongoing feature requests.
Earlier
Government e-services portal (2024 – 2025): built about 70% of the Next.js frontend, with district-level access.
Event ticketing for a Swiss telecom (2023 – 2024): raised unit test coverage from 0% to 60% and cut SonarQube issues from 400+ to under 50.
Open source
azure-keyvault-backup. Python tool that backs up Azure Key Vault secrets. Written for a production project.
Full-time competitive programmer from 2018 to 2022, 1,700+ problems solved, mostly in Java. Then a problem setter and judge for national programming contests in Bangladesh, and coordinator of BD Girls' Coding (2022 – 2023).
All 1,337 of my accepted Codeforces solutions are archived on GitHub, dated when I solved them. competitive-programming
